Communication networks have evolved over time to provide multiple mixed services to end users. Such networks, which once provided only analog broadcast television, have been adapted to provide new services such as digital television broadcasts, on-demand entertainment, interactive television, and data networking. To support different groups of users at different phases of network growth, networks have maintained support for legacy services (e.g., analog television), while simultaneously supporting new services (e.g., data networking). As new services and users are added, such networks may become bandwidth-limited.
In order to expand services further, this disclosure identifies and addresses a need to more efficiently utilize allocated frequency spectrum within communication standards, and to develop new techniques for utilizing unallocated frequency spectrum.